The full form of LOL is "Laugh Out Loud". It is an acronym that originated from the early days of the internet and quickly spread to mainstream usage. It is a very common internet slang used in chatting on the internet. LOL is used to indicate laughter or amusement in response to a particular remark, joke, or situation. It can be used as an interjection and a verb. Even though it means laugh out loud, LOL is mostly used to indicate smiling or slight amusement. It is not a word youd want to use in formal communication, and there are no hard rules about how to capitalize it in informal communication. LOL is also used in spoken language, even though saying LOL creates a contradictory situation where youre saying that youre laughing out loud instead of actually laughing out loud.